- 12 + 3 = - (12 - 3) = - 9
11-15 = - (15-11) = -4
2 - (-10) = 2+10 = 12
-(-3) + 9 = 3+9 = 12
-8-3 = -(8+3) = - 11
3+(-6) = - (6 - 3) = - 3
-5 + (-4) = -(5+4) = -9
0-5 = -5
0+(-7) = -7
-2 + 2 = 0
0 -(-5) = 0+5 = 5
-(-1) - 9 = 1-9 = -8
-7 - (-4) = - 7 + 4 = -3
3 * (-5) = -15
-19 * 2 = - 38
-5*0 = 0
-7 * (-2) = 14
-11*1 = -11
18 : (-2) = - 9
-27 : (-7) = 27/7 = 3 6/7
1) если "а"=-1 и "б"=1,то -1+1>-1
2)если "а"=1 и "б"=-1,то 1+(-1)<1
3)если "а"=1 и "б"=0,то 1+0=1
4)если "а"=1 и "б"=-1,то 1+(-1)=0